This took me ages.
I found HTML generators and plain text lists of all the countries, but no arrays. So I had to make my own. I’m making a website using CodeIgniter, which can use an array to create a select/dropdown field. Get CodeIgniter here, because it is incredibly handy.
Anyway, here it is, prepare to scroll!
$countries = array(
'Afghanistan' => 'Afghanistan',
'Albania' => 'Albania',
'Algeria' => 'Algeria',
'Andorra' => 'Andorra',
'Angola' => 'Angola',
'Antigua & Deps' => 'Antigua & Deps',
'Argentina' => 'Argentina',
'Armenia' => 'Armenia',
'Australia' => 'Australia',
'Austria' => 'Austria',
'Azerbaijan' => 'Azerbaijan',
'Bahamas' => 'Bahamas',
'Bahrain' => 'Bahrain',
'Bangladesh' => 'Bangladesh',
'Barbados' => 'Barbados',
'Belarus' => 'Belarus',
'Belgium' => 'Belgium',
'Belize' => 'Belize',
'Benin' => 'Benin',
'Bhutan' => 'Bhutan',
'Bolivia' => 'Bolivia',
'Bosnia Herzegovina' => 'Bosnia Herzegovina',
'Botswana' => 'Botswana',
'Brazil' => 'Brazil',
'Brunei' => 'Brunei',
'Bulgaria' => 'Bulgaria',
'Burkina' => 'Burkina',
'Burundi' => 'Burundi',
'Cambodia' => 'Cambodia',
'Cameroon' => 'Cameroon',
'Canada' => 'Canada',
'Cape Verde' => 'Cape Verde',
'Central African Rep' => 'Central African Rep',
'Chad' => 'Chad',
'Chile' => 'Chile',
'China' => 'China',
'Colombia' => 'Colombia',
'Comoros' => 'Comoros',
'Congo' => 'Congo',
'Costa Rica' => 'Costa Rica',
'Croatia' => 'Croatia',
'Cuba' => 'Cuba',
'Cyprus' => 'Cyprus',
'Czech Republic' => 'Czech Republic',
'Denmark' => 'Denmark',
'Djibouti' => 'Djibouti',
'Dominica' => 'Dominica',
'Dominican Republic' => 'Dominican Republic',
'East Timor' => 'East Timor',
'Ecuador' => 'Ecuador',
'Egypt' => 'Egypt',
'El Salvador' => 'El Salvador',
'Equatorial Guinea' => 'Equatorial Guinea',
'Eritrea' => 'Eritrea',
'Estonia' => 'Estonia',
'Ethiopia' => 'Ethiopia',
'Fiji' => 'Fiji',
'Finland' => 'Finland',
'France' => 'France',
'Gabon' => 'Gabon',
'Gambia' => 'Gambia',
'Georgia' => 'Georgia',
'Germany' => 'Germany',
'Ghana' => 'Ghana',
'Greece' => 'Greece',
'Grenada' => 'Grenada',
'Guatemala' => 'Guatemala',
'Guinea' => 'Guinea',
'Guinea-Bissau' => 'Guinea-Bissau',
'Guyana' => 'Guyana',
'Haiti' => 'Haiti',
'Honduras' => 'Honduras',
'Hungary' => 'Hungary',
'Iceland' => 'Iceland',
'India' => 'India',
'Indonesia' => 'Indonesia',
'Iran' => 'Iran',
'Iraq' => 'Iraq',
'Ireland' => 'Ireland',
'Israel' => 'Israel',
'Italy' => 'Italy',
'Ivory Coast' => 'Ivory Coast',
'Jamaica' => 'Jamaica',
'Japan' => 'Japan',
'Jordan' => 'Jordan',
'Kazakhstan' => 'Kazakhstan',
'Kenya' => 'Kenya',
'Kiribati' => 'Kiribati',
'Korea North' => 'Korea North',
'Korea South' => 'Korea South',
'Kosovo' => 'Kosovo',
'Kuwait' => 'Kuwait',
'Kyrgyzstan' => 'Kyrgyzstan',
'Laos' => 'Laos',
'Latvia' => 'Latvia',
'Lebanon' => 'Lebanon',
'Lesotho' => 'Lesotho',
'Liberia' => 'Liberia',
'Libya' => 'Libya',
'Liechtenstein' => 'Liechtenstein',
'Lithuania' => 'Lithuania',
'Luxembourg' => 'Luxembourg',
'Macedonia' => 'Macedonia',
'Madagascar' => 'Madagascar',
'Malawi' => 'Malawi',
'Malaysia' => 'Malaysia',
'Maldives' => 'Maldives',
'Mali' => 'Mali',
'Malta' => 'Malta',
'Marshall Islands' => 'Marshall Islands',
'Mauritania' => 'Mauritania',
'Mauritius' => 'Mauritius',
'Mexico' => 'Mexico',
'Micronesia' => 'Micronesia',
'Moldova' => 'Moldova',
'Monaco' => 'Monaco',
'Mongolia' => 'Mongolia',
'Montenegro' => 'Montenegro',
'Morocco' => 'Morocco',
'Mozambique' => 'Mozambique',
'Myanmar' => 'Myanmar',
'Namibia' => 'Namibia',
'Nauru' => 'Nauru',
'Nepal' => 'Nepal',
'Netherlands' => 'Netherlands',
'New Zealand' => 'New Zealand',
'Nicaragua' => 'Nicaragua',
'Niger' => 'Niger',
'Nigeria' => 'Nigeria',
'Norway' => 'Norway',
'Oman' => 'Oman',
'Pakistan' => 'Pakistan',
'Palau' => 'Palau',
'Panama' => 'Panama',
'Papua New Guinea' => 'Papua New Guinea',
'Paraguay' => 'Paraguay',
'Peru' => 'Peru',
'Philippines' => 'Philippines',
'Poland' => 'Poland',
'Portugal' => 'Portugal',
'Qatar' => 'Qatar',
'Romania' => 'Romania',
'Russian Federation' => 'Russian Federation',
'Rwanda' => 'Rwanda',
'St Kitts & Nevis' => 'St Kitts & Nevis',
'St Lucia' => 'St Lucia',
'Saint Vincent & the Grenadines' => 'Saint Vincent & the Grenadines',
'Samoa' => 'Samoa',
'San Marino' => 'San Marino',
'Sao Tome & Principe' => 'Sao Tome & Principe',
'Saudi Arabia' => 'Saudi Arabia',
'Senegal' => 'Senegal',
'Serbia' => 'Serbia',
'Seychelles' => 'Seychelles',
'Sierra Leone' => 'Sierra Leone',
'Singapore' => 'Singapore',
'Slovakia' => 'Slovakia',
'Slovenia' => 'Slovenia',
'Solomon Islands' => 'Solomon Islands',
'Somalia' => 'Somalia',
'South Africa' => 'South Africa',
'Spain' => 'Spain',
'Sri Lanka' => 'Sri Lanka',
'Sudan' => 'Sudan',
'Suriname' => 'Suriname',
'Swaziland' => 'Swaziland',
'Sweden' => 'Sweden',
'Switzerland' => 'Switzerland',
'Syria' => 'Syria',
'Taiwan' => 'Taiwan',
'Tajikistan' => 'Tajikistan',
'Tanzania' => 'Tanzania',
'Thailand' => 'Thailand',
'Togo' => 'Togo',
'Tonga' => 'Tonga',
'Trinidad & Tobago' => 'Trinidad & Tobago',
'Tunisia' => 'Tunisia',
'Turkey' => 'Turkey',
'Turkmenistan' => 'Turkmenistan',
'Tuvalu' => 'Tuvalu',
'Uganda' => 'Uganda',
'Ukraine' => 'Ukraine',
'United Arab Emirates' => 'United Arab Emirates',
'United Kingdom' => 'United Kingdom',
'United States' => 'United States',
'Uruguay' => 'Uruguay',
'Uzbekistan' => 'Uzbekistan',
'Vanuatu' => 'Vanuatu',
'Vatican City' => 'Vatican City',
'Venezuela' => 'Venezuela',
'Vietnam' => 'Vietnam',
'Yemen' => 'Yemen',
'Zambia' => 'Zambia',
'Zimbabwe' => 'Zimbabwe'
);
I hope this helps at least one person. 
